What is atomic mass?

And we can define that $\text{1 amu}$ as the mass possessed by ONE protium atom, i.e. ""^1H. And $\text{Avogadro's number}$ of ""^1H ATOMS have a mass of $1 \cdot g$..
And $\text{Avogadro's number} \equiv 6.022 \times {10}^{23} \cdot m o {l}^{-} 1$ ...we use the $\text{mole}$ as the link between the world of atoms and molecules, and the macro world of grams and kilograms...